Pan loading device



F. D. MARASSO PAN LOADING DEVICE A ril 27, 1965 9 Sheets-Sheet lJE'NTOR.

@m /wg v3 @m Original Filed May 21, 1956 FRED D. MARASSO BY W ATTORNEYApril 27, 1965 F. D. MARASSO 3,180,522

PAN LOADING DEVICE Original Filed May 21, 1956 9 Sheets-Sheet 2 /34 4 40/&0

FIG. 18 p %H ha!) L r a s i M ,V/

k'r fir K98 a4 M8 INVENTOR.

l Ado 08 M2 FRED 0. MARASSO BY f%4/ ATTORNEY April 7, 1965 F. D. MARASSO3,180,522

PAN LOADING DEVICE Original Filed May 21, 1956 9 Sheets-Sheet 3INVENTOR.

FRED D. MARASSO ATTORNEY FIG. 3

April 27, 1965 F. D. MARASSO 3,130,522

PAN LOADING DEVICE Original Filed May 21, 1956 9 Sheets-Sheet 4 FIG. 4

FRED D. MARASSO BY ATTORNEY April 27, 1965 F. D. MARASSO 3,180,522

7 PAN LOADING DEVICE Original Filed May 21, 1956 9 Sheets-Sheet 6 FIG. 8

: INVENTOR.

FRED D. MARASSO BY yM 6W4 ATTORNEY April 27, 1965 F. D. MARASSO PANLOADING DEVICE 9 Sheets-Sheetw 7 Original Filed May 21, 1956 FIG.

FIG. I2

FIG.

INVENTOR. FRED D. MARASSO ATTORNEY April 27, 1965 F. 0. MARASSO PANLOADING DEVICE Original Filed May 21, 1956 FIG. 20

9 Sheets-Sheet 8 FRED D. MARASSD ATTO RNEY April 27, 1965 F. D. MARASSOPAN LOADING DEVICE 9 Sheets-Sheet 9 Original Filed May 21, 1956 FIG. 22

FIG. 23

INVENTOR.

FRED D. MARASSO BY ATTORNEY United States Patent 3,186,522 PAN LGADINGDEVKGE Fred B. Marasso, Richmond, Va, assignor, by mesue assignments, toAmerican Machine 3: Foundry Company, New York, N.Y., a corporation ofNew .lersey Original application May 21, 1956, Ser. No. 586,083, nowPatent No. 3,tl58,614, dated Nov. 16, 1962. Bivided and this applicationFeb. 20, 1962, Ser. No. 174,592 6 Claims. (Cl. 221-106) This applicationis a. division of application Serial No. 586,083 filed by me on May 21,1956 for a Pan Loading Device, now Patent 3,058,614, granted November16, 1962.

This invention relates to loading objects one by one onto a conveyor andmore particularly relates to a device whereon objects may be stackedadjacent the conveyor and loaded from the stack onto the conveyor one byone.

A particular object of the invention is to provide a means forautomatically removing pans from a stack of pans and depositing them oneby one on the pan conveyor of a bakery panning machine.

In the bakery industry machines have been provided whereon pans areplaced in seriatim on a conveyor and conveyed forward to a panningstation where the pans are filled, as for example with a bakery dough.These pans are brought to the machine in nested or stacked arrangement.Heretofore it has been necessary to handload them onto the pan conveyor.Pans in such a nested stack are difilcult to separate since they fitinto each other in very close contact. It is therefore an object of thisinvention to separate pans from said stack one by one in order that theymay be transferred to the conveyor.

In a bakery, pans of varying size are used depending on the type ofgoods to be baked. Accordingly, any automatic equipment must beadaptable to handle various sized pans. It is therefore an object of theinvention to devise a storage and loading device capable of handlingpans of various sizes.

It is also an object of this invention to provide timing means so thatthe pans may be loaded promptly and in rapid succession if required andalso in the event of momentary slowdown of the conveyor, the loadingmust be halted automatically so that one pan is not deposited on top ofthe preceding pan.

A further object of this invention is to devise a pan loading devicecapable of storing a large quantity of pans for ready movement to thetransfer station from which they are loaded onto the conveyor.

It is still another object of the invention to provide a detachablesection of the storage compartment which may be loaded at a distancefrom the machine and brought to the machine.

Still another object of the invention is to provide signal means thatwill alert an operator when the supply or reservoir of pans is low.

It is a further object of the invention to devise a readily adjustablebut durable guide means to accommodate to varying sizes of pans.

It is still another object of the invention to provide such a machinethat is of simple and inexpensive construction.

It is still another object of the invention to design novel pan grippingmeans that will lift one pan from the top of a stack.

Still another object is to provide means for following the decreasingheight of a stack of pans so that the pan gripping means willautomatically grip the first as well as the last pan from a stack.

It is therefore an object of my invention to devise a machine forconveying stacks of pans in a position adjacent a pan conveyor and toautomatically transfer said ice pans from said stacks one by one inseriatim and in properly timed relation to the demands of said conveyor.

In the accompanying drawings:

FIG. 1 is a side elevation partly in section of the automatic pan loaderillustrated in connection with a pan receiving conveyor;

FIG. 2 is a front elevation of the automatic pan loader;

FIG. 3 is a perspective front view of the infeed conveyor of theautomatic pan loader;

FIG. 4A is a circuit diagram of the switcher controlling the automaticpan loader;

FIGS. 4 and 5 when joined at line A-A represent a sectional sideelevation of the entire automatic pan loader showing the movable anddetachable storage and infee conveyor;

FIG. 6 is a partial plan view of a portion of the storage conveyor andthe infeed conveyor of the pan loader in detached position illustratingtheir latching mechanism;

FIG. 7 is a side elevation of FIG. 6 with the portion of the auxiliaryconveyor partly in section illustrating the adjustability of the guideposts;

FIG. 8 is a detailed front elevation of the pan gripping, conveying andreleasing mechanism;

FIG. 9 is a plan view of a pair of pan gripper fingers;

FIG. 10 is an end elevation of the same;

FIGS. 11, 12, 13, 14 and 15 are front elevations of the pan gripperfingers illustrating the sucessive steps in contacting, gripping andlifting a pan from a stack;

FIG. 16 is a partial side elevation of the pan gripper carrying chainillustrating the novel engaging and disengaging arrangements of thechain with the pan gripping device;

FIG. 17 is a sectional end elevation illustrating the pan feed controlmechanism;

FIG. 18 is a partial sectional side elevation of a portion of thedelivery conveyor, illustrating the pan delivery control mechanism;

FIG. 19 is a front elevation of a modified pneumatically operated panloader employing gripping fingers;

FIG. 20 is a plan view, partly in section, illustrating the pan carryingarm, taken on line Zh-Ztl of FIG. 19;

FIG. 21 is a side elevation of the pneumatic control instruments, takenon line 2121 of FIG. 19;

FIG. 22 is a plan view of the modified pneumatic pan loader;

FIG. 23 is a front view of a modified magnetic pan gripper arrangement;

FIG. 24 is an end elevation of the same taken on line 24-24 of FIG. 23;

FIG. 25 is a detailed plan view of one of the magnetic grippers, takenon line 2525 of FIG. 23;

FIG. 26 is a front elevation of a modification of a portion of FIG. 19employing magnets instead of finger grippers.

With reference to the drawings, the automatic pan loader consists of apair of suitably shaped spaced frames 20 within each of which is housedan endless conveyor chain 22 each of which is driven by a sprocket 24.Both sprockets 24 are mounted on a transverse horizontal drive shaft 26.Shaft 2d carries a pulley 28 driven through belt 36 from a Reeves pulley32 which is similar in its function to that shown in US. Patent No976,596 issued Nov. 27, 1910 to George H. Pertuiset. This pulley 32 ismounted on a shaft 34- projecting from the housing of a suitable gearreduction motor 35 secured to a pair of brackets 38 slidably supportedby a pair of rods 40 held by a pair of suitable bearing flanges 42integral with the frame of the machine. Motor brackets 38 also engagewith a threaded spindle 44 rotatably supported in bearing flanges 4-2.Spindle 44 has a hand wheel 46 for turning spindle 44 to effect a backand forth movement of the gear reduction motor 36 whose supportingbracket 38 engages with said spindle 44. Since pulley -32 is of theReeves type, this provides a variable speed control for the'conveyorchains 22.

The chains 22 are first guided vertically up and over sprockets 48 and50 and then around sprockets 52 and 54 to form a horizontal loop atright angles to the vertical run.

'All sprockets 48, 50, 52 and 54 arerotatably supported, respectively,by short stud shafts 62, 56, 58 and 60' suitably secured in the frames20. In order to assure that the vertical runs of the chains are exactlyparallel, each chain is also led over an additional guide sprocket 64rotatably supported by a stud shaft 66, each held by the respectiveframe 20'. V

Each chain 22 is provided with two angle brackets 68 (FIGS. 8, l6 and17) secured thereto and spaced half the length of the chain apart. Eachbracket 68 carries a pin or stud 70 projecting horizontally towards thecenter of the machine and opposite the stud 70' of the other chain toform a pair to support horizontally a gripper finger supporting andcarrying bar 72. Integral with each end of each gripper fingersupporting bar 72 is a carrier bracket 74Vthe free end of which isprovided with a vertical pin engaging plate 76 (FIGS. 8, 9, 16 and 17)having a wedge shaped pin receiving slot 78 by means of which each ofthe two gripper finger supporting bars 72 are carried by the two pairsof opposed studs '70 on the spaced endless conveyor chains 22.

Each bar 72 supports a pairof slidably mounted gripper finger carriermembers 80 (FIGS. 8, 9 and which support a stationary mounted horizontalshaft 82 projecting from each side of said member 80. To each projectionof shaft 82 is pivot-ally mounted a pan gripper finger 84 each of whichin a sense is a double lever of which the bottom end is formed as a pangripping hook 86 while the curved top end portion 88 serves asa-disengaging means. Each gripper finger is provided with torsion spring90 one end of which contacts the top edge of the lower portion of thegripper finger while the other end is secured to a suitable collar 92mounted to each end of each projection of the stationary shaft 82. Thetorsion 4 a the chain reach the pin gripper supporting bar 72, said pinsagain engage with the slots 78 of plate 76 and upon continued travel ofthe chains 22 carry said bar upward. As the gripper finger carrying baris lifted oif the stack of pans, the top pan of said stack is engaged bythe gripper fingers and carried upward also. As illustrated in FIG. 16,the distance between the vertical down run D and vertical up run U ofthe chains is so calculated and arranged that thevertical up or downmovement of the pins 70 always move over the same verticalpath asindicated by the dot-and-dash lines M (FIG. 16); thus the pins 70 movingwith the chains can easily disengage from the plates 76 on theirdownward movement and readily re-engage on their upward movementregardless of whether the stack of pans is high or low.

The finger carnier members 80 on the supporting bars 72 are so set thatwhen said bar is lowered by the chains 22 onto the stack of pans thelower curved edges 87 of the hook portion 86 of each gripper finger 8-contacts the inner edge of the topmost'pan P of the stack first asillustrated in FIG. 11. As bar 72 continues its downward travel saidlower edges 87 of fingers 84 slide in a cam like motion over the topedges of said pan as shown in FIG. 12 until the hook portion 86 offingers 84 slide over the outer edges of the rim of the pan as shown inFIG. 13. The bar 72 continues its downward travel until thetWo'U-sh-aped stabilizer rods 106, one of'each of which is secured toand suspended from each carrier member 80, contacts the rims of the toppan P on the springs 90 have the tendency to urge the pan gripping hook86 of the fingers 84 downward in such a manner that the gripping hooks86 of the two pairs of gripper fingers which oppose each other on agripper finger supporting bar 72 are urged towards each other to gripand hold a pan between them as illustrated in FIG. 8. A suitably shapedplate 94- extending horizontally from the top portion of each carriermember 80 serves as a stop to limit this spring urged movement.

As mentioned heretofore, it is the object of the automatic pan loader topick up the pans P one by one from a stack S placed in the machine andcarry and deliver them to a suitable conveyor C. The latter may consistof a pair of endless parallel spaced and continuously driven conveyorbelts 96 supported by a suitable table 98of a frame 180 and guided overa pair of pulleys 192. Belts 96 are driven by suitable driving pulleys103 (FIG. 8) connected to a suitable source of power (not shown).

When a pan P is to be picked up from the top of the stack S the gripperfinger supporting bar 72, of course, is travelling downward towards saidstack and the angle brackets 68 which by means of pins 70 carry said bar72, are on the vertical downward run-of the chain 22 indicated by thearrow D in FIG. 16. When the gripper finger carrying bar 72'reaches thestack it simply comes to rest on top as illustrated in FIG. 2 while thepins 70 of the angle brackets 68- on chain 22 disengage from the slots78 of the plates 76 as the chain continues its downward movement. Afterthe pin carrying angle brackets 68 on chains 22 travel around thesprocket 24 said brackets, of course, move upward again with the chainin the direction indicated by the arrow U in FIG. 16. When the pins 70on brackets 68 moving upward with stack and causes the arrest ofsaid barwhile the pins 7 t), which support the bar and are secured throughbrackets 68 on the chains 22,. disengage from said bar and continuetheir downward movement as described heretofore. In this position thelower side edges 89 of fingers 84 rest on the top edges of the rim ofthe top pan P. as illustrated in FIG. 14 and also in FIG. 2.

The pins move upward again to lift gnipper finger supporting bar fromthe top of the stacks. As the bar is lifted from the rim of the top pan,the torsion springs 98 of the gripper fingers 84 are urged downward,thus causing the lower side edges 89 to remain in contact with the rimof the pan until the hook portion 36 engages with the rim to lift thepan from the stack with the bar 72 as illustrated in FIGS. 15 and 8.

Each bar 72 supports two sets of fingers so that they are able to engagewith the rim portions on the opposite ends of each pan as illustrated inFIG. 8. In order to v provide means to accommodate pans of differentlengths 110 through the hole 109 in the carrier 80 and the selected hole108 in the bar 72 various desirable distances between the opposed pairsof fingers on each bar may be obtained. It may also be pointed out thatthe hook 86 is shaped so that the engagement and sliding action of thelower hook edges 87 of the fingers 89 over the top. edges of the rim ofthe pan during the lowering of the bar onto the pan keep the panengaging hook fairly sharp and eflioient.

After being lifted from the top of the stack S, the pan P is carriedupward-in a vertical direction which, after the pin supporting brackets68 on chain 22 have passed around the sprocket 56, changes to ahorizontal direction towards the conveyor C. As the pan P reaches aposition approximately above the conveyor belts 96 the upward projectingends 88 of the gripper fingers 84 pass beneath and contact a \pair ofsuitably curved release ac-- tuating plates 112 (FIGS. 2, 4 and 8)causing a depressing of fingers .94 as illustrated in dotted lines inFIG. 8. to disengage the hook portions 86 from the rim of the pan Pwhich then, of course, drops onto the moving. conveyor belts 96 as shownin dotted lines in FIG. 8 which carry the pan away to an appropriatestation for any d.i-

i3 sired purpose. The release actuating plates 112 are secured to astationary horizontal cross bar 11 (FlGS. 4 and 8) which at its end ismounted on and supported by the studs 53 which also support thesprockets 52.

In order to prevent excessive whipping of the pan P as the chains, whentravelling around sprockets Stl, change the path of said pan from avertical to a horizontal direction, a curved guide bar is provided(FlGS. 2 and 4). This bar ill? is adjustably clamped to a bracket 118which may be integral and project from a cross bar 12%? secured at eachend to the front face of each of the two frames 2%. While being carriedthrough its horizontal path towards the conveyor C the pan is preventedfrom swaying or swinging by means of a top guide rail 122 (FIGS. 4 and8) which is suspended by two suitable spring posts 124 one of which isheld by the cross bar 114 while the other is attached to a cross rod 125held at each end by the frames 29.

In order to prevent sagging of the chains 2.2 and assure a perfecthorizontal path of the pan when carried towards the conveyor C, thechains 22 during their horizontal run are supported by suitable guiderails 128 and 13%? (FIGS. 1 and 17) secured by suitable studs 132 to theframes 26.

After the pan P is dropped from the gripper fingers 84 onto the conveyorbelts 96 of the conveyor C, said fin ers, of course, travel with thechains around the sprockets 52 and 54 and after running over sprocket 43descend vertically towards the stack S to pick up another pan in thesame fashion in an alternate subsequent cycle as described above.

In case same delay occurs in serving one of the leading pans of the rowof pans on the conveyor C, timing means are employed to prevent a panbeing dropped on the conveyor C before the one previously deliveredthercto has moved away. The timing means to automatically obtain suchdesired delay in pan delivery consist of two normally closed switches134 and 136. Switch 136 is suitably attached to the underneath side ofthe table d of the conveyor C while the switch 134 is suitably securedwithin one of the frames (FIGS. 1, 2, 17 and 18).

Switch 13-6 is activated by means of an arm- 138 mounted on a shaft 14%rotatably supported by a pair of bearing brackets 142 fastened to theunderside of the conveyor table 98 (FIGS. 1 and 18). To shaft 149 isalso secured a feeler finger 144 which with its free end projectsthrough a slot 146 in table 2 8 between the two conveyor belts 96 intothe path of the pan P conveyed by belt 96. One end of a suitable torsionspring 148 bears on the feeler 144 while the other end is anchored toone of the bearing brackets 142 to urge the feeler 14- in the path ofthe pans with arm 138 away from the contact but-ton of the normallyclosed switch 136.

The switch 134- is kept normally closed by means of an engagement of itscontact button with the upper end of an arm 150 which in its centralportion is pivotally mounted on a stud 152 held by and projecting from aframe portion of the machine. To the lower end of arm 150 (FIGS. 1 and17) is pivotally attached one end of a bar 154 while the other end ofsaid bar is pivotally attached to the free end of a short arm 1% whichis loosely supported by a stud 153 so that the bar 154 is suspendedhorizontally and parallel to chain 22 as illustrated in FIG. 1. In orderto keep the free end of arm 150 in engagement with the contact button ofthe switch 134 to maintain the characteristics of a normally closedswitch a tension spring 16% attached to bar 154 and anchored to theframework is provided. The two switches 134 and 136 are connected inparallel to a conventional motor control circuit located in the motorcontrol box 162 attached to one of the frames 20 of the machine.

The timing and control of the pan delivery to the conveyor C operates inthe following manner: As mentioned above, a pan P picked from the stackS by the gripper fingers 84 is carried upward first in a verticaldirection and then, after passing sprockets 56, in a horizontaldirection. The bar 154 in its normal down position lies in the path ofone of the pins 70 which project from the chains 22 and carry thegripper mechanisms and pan. As the pin 7th contacts the leading roundededge of the bar 154 it presses the same backward as well as upward untilit rides beneath said bar and the latter in somewhat raised positionrests on the top of the moving pin as illustrated in FIG. 17. Thisraising of bar 154 causes the free end of arm 15%) to disengage from thecontact button of switch 134, thus effecting an opening of the normallyclosed switch 134. Since the switches 134 and 136 are connected inparallel to the motor control circuit, the closing of either one willenergize the motor 36 to drive the pan loader chains 22. Now, if whileswitch 134 is open, there should be a pan on the conveyor belts ridingor stopping over the feeler finger 144 to open switch 136, the motorwould stop and thus arrest the pan loader chains 22 in a positionbeneath bar 154. Thus no pan would be delivered until finger 144 wascleared. The location of bar 154, however, means that a pan is beingheld ready for prompt delivery when required.

There is also provided on front plate 166 a manual switch 164 forstopping the machine (FIGS. 2 and 4). Switch 164 is in series withswitches 134 and 13s. The circuit diagram shown in FIG. 4a illustrateshow these switches are connected.

The stacks of pans S, S FIG. 1, are placed in the machine on a platformE against vertical side and back guides 16% and 176 respectively. Theplatform E itself consists of a row of parallel mounted rollers 172which are rotatably supported by means of a pair of spaced parallelrails 174 which are integral with and form a part of the bottom frame176 of the machine. The vertical side frames 24 are also secured to thebottom frame 176 so that it forms the support for the entire machine.

To facilitate the moving of the pan loader to a machine or conveyorwhere its services are needed, the bottom frame 176 is provided with anumber of suitable casters or rollers 178. To prevent accidentialmovement of the pan loader after it is placed adjacent a machine orconveyor the bottom frame is also provided with a pair of spindle jacks18% which may be manipulated by the operator by means of suitablehandwheels 132 to effect a positive stationary placement of the panloader.

The vertical back guides 17% are mounted on a pair of cross members 184(FIGS. 1, 3 and 4) which are adjustably secured to suitable supportingbrackets 186 fastened to the vertical side frames 21? of the machine.Each of the vertical side guides 163 is at its bottom end secured to abottom guide rail 188 (FIGS. 2 and 3), each of which is mounted on apair of lugs 19%). The forward lugs of the rails are supported by andengage with the threaded portion of a horizontal spindle 192 while thebackward lugs of said rails are supported by and engage with thethreaded portion of a spindle 194. Both spindles 192 and 194 arerotatably supported in suitable bearings provided in bottom frame 175.To one end of each spindle is secured a sprocketlllfi. The sprockets areinterconnected by means of an endless chain 1% (FIG. 3) while thespindle 192 also carries a handwheel 2%. Each spindle 192. and 1% isprovided with a right-hand threaded portion and a left-hand threadedportion and the bottom rails 18% are so arranged that the lugs 19%) ofthe left side rail engage with the left-hand threaded portions of bothspindles while the lugs 1% of the right side rails engage with theright-hand threaded portions of both spindles. By turning the handwheel2439 the bottom rails 188 may be brought closer together or furtherapart to provide proper guidance for the particular size of pans to beused in the machine.

As illustrated in FIGS. 4 and 5 the roller platform E is of sufficientlength to accommodate three stacks of pansso that after the last pan ofthe stack S is lifted from the platform a new stack S1 can be pushedinto place without the necessity of stopping the machine.

An alarm or call system is provided to signal an attendant when thereare only four or five pans left on the platforms so that he can stand byand push in a new stack after the last pan from the previous one islifted. The alarm or signal system consists of a suitable switch 202which is provided with a spring loaded actuating member 204 whichengages with the rear edges of the pans close to the bottom portion ofthe stack S (FIGS. 3 and 4). The switch 202 may be connected through atransformer 206 (FIG. 1) to a suitable signal device such as a bell 208illustrated in FIG. 1. So long as the switch actuating member 204 isdepressed by and in engagement with the rear edges of the pans of thestack S, the switch 202 is open, but as soon as the pans are liftedaway, the arm 204 swings forward and effects a closing of switch 202which in turn causes the bell 208 to summon the attendant. The bell 208,of course, may be replaced by a light or any other desirable signaldevice.

7 Since the pan loader illustrated in the drawing is chiefly used inbakeries where dough particles and flour dust may gum up the drivingmechanism, the two vertical side frames 20 which house the liftingchains and other mechanisms are closed on the inside with suitableplates 210 while the outside of said frames are covered by means ofhinged doors 212 to provide ready access for servicing. This arrangementalso prevents any grease or oil from the mechanisms to drop or splash onthe pan into which food is deposited later on.

Since the automatic pan loader illustrated in the drawing has proven tobe a fast and trouble-free pan feeding device, it also has beenexperienced that its economy and efficiency may be utilized to a greaterextent by having additional stacks of pans in readiness for feeding intothe machine. For this reason the machine may be provided with a movableand detachable storage and infeed conveyor releasably secured tothe'free end of the roller platform E. The storage and infeed conveyor Fillustrated in FIG. 5 consists of a suitable rectangular frame 22%)mounted on four rollers or casters 222.

The frame 220. rotatably supports a row of rollers 224 of the same typeas the rollers 172 of the platform E. To the rear of the frame 220 issuitably secured a U-shaped handle bar 22d employed for the purpose ofmanually pushing or moving the infeed conveyor when detached from themachine.

' The front end of the infeed conveyor also loosely carries a stackmetering rail which consists of two spaced vertical tubes 228 which attheir top end are connected to a horizontal cross tube 230. Adjacentboth sides of the extreme forward end of frame 220 are suitably securedtwo horizontal plates 232 to each of which are mounted three equallyspaced upright studs 234, 236 and 238 to any pair of which the lowerends of the vertical tubes 228 may be engaged. Adjacent to the lower endof each of the two vertical tubes 228 is also secured by welding or.

similar means a short tube or bushing 240 which also may be engaged withany of the three pairs of upright studs 234, 236 and 238. As illustratedin FIG. 5 the stacks of pans carried by the infeed conveyor F are placedfairly closely against each other and are confined between thestationary mounted upright tubesof the handle bar 226 and the verticaltubes 228 of the metering rail, thus preventing tilting or shifting ofthe stacks of pans while being moved on the auxiliary infeed conveyor.In order to maintain this stack confinement feature when pans of asmaller or larger size are used the vertical tubes 228 or their adjacentsmaller tubes 240 may be brought in engagement. and placed on any of thethree pairs of upright studs 234, 236 and238 to acquire the correctdistance between said vertical tubes and the stationary parts of handlebar 226 to accommodate the size of pans to be used. With the arrangementshown in FIGS. 5, 6 and 7, nine different positions of the verticaltubes 228 may be obtained or stated otherwise through positions on eachof the studs 234, 236 or 233. FIG. 7 illustrates in dotted lines how thevertical tubes may be placedon the different upright studs. Thearrangement in dotted lines at 238 in FIG. 7 is obtained by reversingside for side the vertical tubes 223.

Since the height of the stacks of pans to be pushed into the pan loaderis limited, the horizontal cross tube 230 serves as the metering bar forthe height of the stacks to be placed on the movable infeed conveyor sothat any guesswork concerning the height of the stacks is eliminated.

In order to properly connect the infeed conveyor F to the end of theroller platform E, the extreme ends of the roller platform rails 174 areprovided with a pair of latch hooks 242, FIGS. 3 and 7, which aresecured to and extend from the ends of said rails 174. The forward endof the infeed conveyor F is provided with a horizontal latch bar 244which at each end is secured to a lug 246 which is pivotally attached tothe side end portion of frame 220 by means of a bolt 248. A suitabletension spring 250 is employed to keep the latch bar 244 in the raisedposition illustrated in FIGS. 5 and 7.

In order to connect the movable conveyor F to the end of the rollerplatform E of the pan loader, the attendant simply pushes the front endof the conveyor F against the end of the platform E and the latch bar244 due to its yieldable mounting will engage with the latch hooks 242extending from the rails 174 'of the roller platform E. To detach theconveyor F from the pan loader the attendant simply steps on the latchbar 24-4 and depresses it while moving the conveyor backwards.

The modified pan loader illustrated in FIGS. 19, 20, 21 and'22 is of thepneumatic type and consists of a vertically reciprocating trolley 264which carries two pairs of suitable rollers 262 which engage with avertical hollow square post 264. The latter on its top and bottom ispro-- vided with a stud shaft 266 and 263 respectively. Stud 266rotatably engages with a suitable bearing plate 270 secured to the upperpart of'a suitable bridge frame 272. The stud 268 on the lower end ofpost 254 rotatably engages with a suitable bearing 274 (FIG. 19).

To the free end of the stud shaft 266 on the upper end of the post 264is secured an arm 276 the free end of which is pivotally connected tothe end of a piston rod .278 which carries a piston 28%) (FIG. 22)engaging with by a bracket 2% secured to the bridge frame 272. Air

valve 294 is connected to an air supply control panel A (FIG. 21). Thesolenoidactuated air valve 294- is a conventional type valve, such asthe Electroaire manufactured by the Bellows Co. of Akron, Ohio. 7

The trolley 26% is provided with a pair of vertically spaced lugs 298which yieldingly engage with the free end of a piston rod Silt)connectedwith a piston 392 in a closed vertical cylinder 34M. Cylinder364, by means of a pair of. suitable brackets 3% is held by and securedto the vertical post 264 (FIG. 19). The yieldable connection of the freeend of the piston rod 3% and the lugs 22% of the trolley consistof a nut56% at the end of rod 300, a sleeve 312 secured to said rod and acompression spring 319 (FIG. 19) surrounding the end portion of said rodand being confined between the lower lug 298 and the lower end of thesleeve 312.

The weight of the trolley 26th is balanced by means of a counter weight314 suspended within the hollow post 264 from one end of a cable 316while the other end of the latter is secured to a cross rod 313 mountedon the trolley 260. The cable 316 is supported by and guided over apulley 329 pivotally held by a pin 32-2 in a suitable lug of the wall ofthe hollow post 264.

The top and bottom ends of the vertical cylinder 394 are connected by asuitable tubing or duct 324 while to the top end of said cylinder isconnected and mounted thereto a two way solenoid controlled air valve325 such as manufactured by the Bellows Co. of Akron, Ohio. Valve 326 bymeans of hose 3-28 is connected to an air supply control panel A, suchas illustrated in FIG. 21 of the drawings.

The trolley 26% is also provided with a pair of suitable arms 33% to thefree end of which is mounted a gripper finger supporting bar 332 towhich in turn are adjustably secured a pair of gripper finger carryingmembers 334- each of which carry a pair of spring mounted gripperfingers 336.

The gripper finger supporting bar 332, the carrying members 334 and thefingers 336 are of the same construction as the bar 72, carrying member80 and fingers 34 shown in FIGS. 8, 9 and 10 used in the preferredembodiment and described heretofore.

The bar 332 also carries in its central portion a floating springmounted pan stabilizing plunger 338 and a pair of spaced adjustablemounted pan guide lugs 34%.

The pans P are assembled in a stack S (FIG. 19) and the object of thepan loader is to transfer said pans one by one from the stack S onto thebelts 342 of a continuously moving conveyor C which may be of the sametype and construction as shown and described heretofore in the preferredembodiment of the machine. The stack S is placed on a suitable platform344 such as illustrated in FIG. 19, which may be the same as E and F inFIGS. 4 and 5.

The operation of the pneumatic pan loader shown in FIGS. 19, 20, 21 and22 is as follows:

When the piston 302 in the vertical cylinder 304 is driven downward, thetrolley Ztl carrying the pan gripper assembly, of course, moves downwardalso until the U- shaped stabilizing members 346 and the gripper fingers336 come to rest on the pan P on top of the stack S (FIG. 19) much inthe same manner as illustrated and described heretofore in the preferredembodiment. Said contact of members 346 and finger 336 naturally causesthe arrest of the trolley 260 while the piston 3G2 and its piston rod 3%have the tendency to go down still further. However, a disc 348 (FIG.19) mounted on and carried by the piston rod 3% contacts and depresses amicro switch 350 which in turn actuates the solenoid air valve 326 insuch a manner as to direct the air stream which pushed against the topof the piston towards the bottom of the cylinder 334 so that the airstream now pushes against the bottom of the piston and thus effecting anupward motion of the piston as well as the trolley and its pan grippingassembly.

As the pan gripping assembly moves upward, the gripper fingers engagewith the pan on top of the stack S in the same manner as illustrated anddescribed in the preferred embodiment heretofore. The pan P is lifteduntil a vertical stud 352 (FIG. 19) carried by the trolley 260 contactsa spring mounted plunger 354 of a micro switch 356 which actuates theair valve 294 (FIG. 22) in such a manner as to direct the air streamthrough hose 2% to enter the forward end of the horizontal cylinder 282which in turn causes the piston 28% to move backward to drive its rod278 and cause a clockwise turning of the arm 276 which since it ismounted on the upper stud 266 of the vertical cylinder 264 effects alsoa clockwise turning of said trolley carrying post 264 until the rearwardedge of mm 276 contacts a micro switch 358 mounted on the bridge frame272. At the time the arm 2% contacts switch 358 the pan P, due to theturning of the post 264, has been brought over the belts of the conveyorC as illustrated in dotted lines in FIG. 22. Also near the end of this90 horizontal swing of the pan and the gripping mechanisms carried bythe trolley 260, one set of closed switch 379 is held open.

1% the gripper fingers 336 engaged with their upper ends with a suitablecurved bar or rod sea which caused a depression of said fingers torelease the pan to drop onto the belt 342 of the conveyor C. The rod 360may be suitably secured to a bracket 362 mounted on the inside of thebridge frame 272 straddling the conveyor C.

The contact of the rear edge of arm 276 with the micro switch 358 causesthe solenoid actuated air valve 2% to shift in such a manner as todirect the air stream from the front of the piston 12% through hose 292to the rear of piston 2% to move it forward. The forward motion of thepiston and its rod 278 causes the arm 276 to rotate counter clockwise,which in turn effects a counter clockwise movement of the trolleycarrying post 264 until the forward edge of said arm 275 contacts amicro switch 3&4 (FIG. 22) which takes place just when the piston 28% inthe horizontal cylinder reaches the end of its forward stroke and thepan gripping mechanism carried by the arms 335') of the trolley 25% isdirectly above the pan stack S. The length of the stroke of the piston28%} forward as well as backward is so calculated as to effect anapproximate 90 turn of the trolley carrying post 264.

When the forward edge of arm 276 contacts the micro switch 364; thelatter causes the solenoid actuated air valve 326 on top of the verticalcylinder 394 to shift in such a manner as to permit the air stream topress against the top of the piston 36?. causing it to move downwardwhich, of course, effects a downward movement of the gripper carryingtrolley until the gripper fin ers contact the top pan of the stack S andarrest said trolley. In this position as mentioned heretofore the microswitch 359 on the trolley (FIG. 19) is closed by the disc 348 on thepiston rod 3% causing an upward movement of the piston 392. andconsequently of the trolley and gripper mechanism which, of course, haveengaged with and lifted the top pan of the stack S, thus repeating thecycle of operation.

In order to avoid the delivery of a pan to the conveyor C before theprevious one has been moved out of the way a spring mounted feelerfinger 366 of the same type and construction as feeler 144 shown inFIGS. 1 and 18 is located on the conveyor C between the belts 342projecting into the path of the pans advanced by the same. Said feeler3&6 (FIG. 19) is connected with an arm 368 in such a manner that thelatter contacts and opens a normally closed micro switch 376 everytirnethe feeler 366 is depressed by a pan riding over the same. The microswitch 37% is connected in series with the switch 356 which is depressedwhen the trolley reaches its uppermost position and which is employed toeffect a turning of the trolley carrying post 264 to swing the pancarried by the same over the conveyor C. Therefore, the closing ofswitch 355 will have no effect when a pan on the conveyor is still overthe feeler finger 36d and the normally In this case the picked up pan isheld over the stack S and all movements stop until the pan on theconveyor rides off the feeler finger 366 and switch 37d is closed again.There is no strain on the mechanism but merely pneumatic pressure onpiston 302 which rests at the top of its stroke in cylinder 3%.

The solenoid actuated valve 294 controlling the reciprocating action ofpiston 280 in the horizontal cylinder 282 is of the three way type sothat when the main switch (not shown) of the machine is switched to off,all air pressure in the unit is released. All air supplied from asuitable source (not shown) is piped to the control panel A by means ofa tube 373.

The mechanical pan gri per mechanism shown and described above in thepreferred as well as the modified embodiment of the automatic pan loadermay readily be replaced by magnetic grippers such as illustrated inFIGS. 23, 24 and 25. In this case the gripper finger supporting bar 372corresponding to the bar 72 in FIG. 8 or bar 332 in FIG. 19 carries apair of slidably and adjustably mounted brackets 374 to the bottom sideof each of which is secured a horseshoe magnet 376. Each bracket 374 ialso carries a stud shaft 378 which pivotally supports a bell crankshaped ejector arm 380 which consists of a pan stripper finger 382 andan actuating lever 384. A torsion spring 386 surrounding stud shaft 378and acting against the actuating lever 384 keeps the latter inapproximately upright position and thestripper fingers well within thehorseshoe concave of the magnet.

As the magnetic gripper fingers are lowered onto the stack of pans themagnets 376 of course pick up the top pan of the stack. As the pancarrying grippers are moved over the conveyor C this actuating finger3S4 comes in contact with a pair of curved release plates similar to the.onesdesignated 112 and shown in FIG. 8 or 360 in FIG.

22which cause said fingers 384 tobe depressed. The

1. A device for picking up the topmost pan from a' stack of panscomprising a pair of endless chains each having a vertical run along theside ofa stack of pans from which the topmost pan is to be removed, saidvertical run extending to the bottom-most pan of the stack, the downwardpass of the vertical run of each chain being substantially parallel tothe upward pass and said vertical runs being spaced apart a certaindistance, means to activate said chains, a support element secured toeach of said chains in parallel relation to each other and extendingfrom the chain a distance substantially half said certain distance in adirection to move along the center line between saidchains on theirvertical parallel runs, a supporting bar having end portions which mayhe engaged and supported by said support elements, so that said bar maybe deposited on the topmost pan contacted during the downward run of thesupport elements and re-engaged during the upward run, gripping meanssecured to said support bar and constructed to grip a tray on which saidsupport barhas rested whereby said support elements may deposit saidsupport bar on a stack of pans during the downward run and lift thetopmost tray on engagement during the upward run of said supportelements, said gripping means comprising a magnet secured to said bar toengage and support in its magnetic field a topmost pan on the stack onwhich said bar was deposited.

2. A device substantially as set forth in claim 1 further characterizedby a stationary plate positioned at a point distant along the run ofsaid chain from said stack of pans to engage and release a pan supportedby said magnets in transit along said chains on said supporting bar todeposit said pan at said position.

nisms comprising a vertical shaft, a slide supporting said support barand verticallyslidable on said vertical shaft, first pneumatic means toliftsaid slide and other pneumatic means to rotate said vertical shaft,said first pneumatic means to drop said vertical slide until saidportions rest on the topmost pan of a stack of pans and control meansthen actuating said first pneumatic means to lift said slide to apredetermined position on said vertical shaft, said otherpneumatic'means responsive to the attainment of said position to thenrotate said vertical shaft about its axis to rotate said slide therewithand said support bar to the delivery station.

4. A device as set forth in claim 3 further characterized in that saidvertical slide is nonrotatably mounted on said vertical shaft.

.5. A device for transferring pans one by one from a stack of pans at aninput station to an output station, said device comprising a rotatablymounted vertical shaft, a slide slidably mounted on said vertical shaftto move therealong, said slide being secured against rotation about saidvertical shaft, a cylinder secured on said vertical shaft and adjacentone cnd thereof and parallel thereto, a piston slidable in saidcylinder, a piston rod secured at one end to said piston and at itsother end to said slide,

3. A device for lifting the topmost pan from a stack 7 of pans at aninput station anddepositing one by one at a delivery station, saiddevice comprising a support bar having gripping means secured thereto,said gripping means having portions adapted to rest on a pan, mechanismsfor moving said support bar from said delivery station to a position inwhich said gripping means rests on the top pan in said stack at saidinput station, means to inactivate said mechanisms when said grippingmeans on said support bar grips the topmost pan of a stack on which saidportions have rested, drive means for said mechanisms, said mechanismslifting said support bar from said stack and moving said support bar andthe pan gripped by said pan gripping means to said delivery station, arelease device operative to release said pan from said gripping means atsaid delivery station, said mechaa source'of fluid under pressure,valvular means communicating with said cylinder and said source tointroduce fluid under pressure to one end of said cylinder and tointroduce fluid under pressure to the other end of said cylinder so thatsaid piston may be driven up and down in said cylinder, a second fluidpiston cylinder, means interconnecting said second cylinder and saidshaft operatively constructed to rotate said shaft through an angularare, a support bar extending substantially horizontally from said slide,pan gripping means on said support bar to grip a pan when said supportbar is lowered so that saidfirst-named fluid cylinder may drop saidgripping means on the top of a stack of pans and lift said grippingmeans, and control means responsive to the lifting of said slide' toactuate said second-named fluid cylinder so as to rotate said slide sothe pans may be deposited at said output station.

6. A support for a stack of baking pans to be transferred one by one toa station remote from said support, traveling means having a magnet forengaging a selected pan for transfer to said station, a first verticallyreciprocable pneumatic operating means and a second horizontallyrotatable pneumatic operating means for said traveling means, meansoperative in response to the downward movement of said first pneumaticmeans and the. engagement of said magnet with a selected pan forinterrupting the travel of said traveling means, means operativeincident to said interruption for actuating said first pneumatic meansto lift said traveling means and said magnet carrying said pan, andmeans responsive to said lifting for actuating said second pneumaticmeans, to rotate said traveling means into a position over said station.

References Cited by the Examiner UNITED STATES PATENTS 1,508,084

9/24 Collis 33126.75

' 2,524,846 10/50 Socke et al. 53247 X 2,615,745 10/52 Fischer.

2,656,060 10/53 Fischer et a1. 214-309 2,815,874 12/57 Kowal 221106 X2,881,929 4/59 Gitfin.

2,980,265 4/61' Johnson et al.

3,031,906 5/62 Holman.

3,058,614 10/62 Marasso 221-218 X 'LOUIS I; DEMBO, Primary Examiner.

HADD S. LANE, Examiner.

6. A SUPPORT FOR A STACK OF BAKING PANS TO BE TRANSFERRED ONE BY ONE TOA STATION REMOTE FROM SAID SUPPORT, TRAVELING MEANS HAVING A MAGNET FORENGAGING A SELECTED PAN FOR TRANSFER TO SAID STATION A FIRST VERTICALLYRECIPROCABLE PNEUMATIC OPERATING MEANS AND A SECOND HORIZONTALLYROTATABLE PNEUMATIC OPERATING MEANS FOR SAID TRAVELING MEANS, MEANSOPERATIVE IN RESPONSE TO THE DOWNWARD MOVEMENT OF SAID FIRST PENUMATICMEANS AND THE ENGAGEMENT OF SAID MAGNET WITH A SELECTED PAN FOR INTER-